1. Field of the Invention
The present invention relates to a technology for binding a paper bundle delivered from a preprocessing device.
2. Description of the Related Art
In connection with a post-processing apparatus connected to an image forming device as a preprocessing device, the following functions are generally known: a function of binding an lateral side end or a lateral side center of a paper bundle with a staple upon receiving a paper bundle delivered from the preprocessing device; a function of performing bookbinding by pressing paper ends onto a sticky tape; and as another bookbinding function, a function of finishing a ring-bound book by punching a plurality of holes on a binding side of a paper bundle, and then binding the paper bundle with a metal coil or plastic rings.
As a paper post-processing apparatus that performs binding processing of a paper bundle with staples, there are apparatuses as described in Japanese Patent Application Laid-open No. S63-41373, Japanese Patent Application Laid-open No. H3-153393, Japanese Patent No. 2723987, Japanese Patent Application Laid-open No. H7-69525, and Japanese Patent Application Laid-open No. 2005-17692, and proposed is a configuration designed to prevent occurrence of a defect in staple processing.
According to a ring bookbinding apparatus used as a post-processing apparatus (see, Japanese Patent Application Laid-open No. 2007-30319, Japanese Patent Application Laid-open No. 2007-31068, and Japanese Patent Application Laid-open No. 2007-55179), rings made from a metal coil or plastic are used, and a user refills rings into a ring cartridge in accordance with consumption of rings.
When setting rings into the cartridge, the rings need to be set by selecting a ring size and a type of ring diameter in accordance with a purpose of bookbinding. There is a possibility of occurrence of a trouble that, for example, the rings are set upside down mistakenly, or rings in the cartridge run out during processing.
A paper bundle of which ring bookbinding is once finished is sometimes added with a sheet of paper by temporarily opening rings in some cases. For this reason, there is a ring bookbinding apparatus configured to accept a mode of performing only punching processing in which paper is delivered by punching a plurality of punch holes in the paper.
In such case, a sheet of paper to be added needs to be punched with a plurality of punch holes appropriate to the size of rings used in the finished ring bookbinding.
Troubles, for example, a mistaken set by user when setting rings in a cartridge, and a shortage of rings during processing, also need to be coped with.